latest company case about Guangzhou Cleanroom Construction Co., Ltd. Certifications

The air shower pass box consists of several major components, including the cabinet, centrifugal fan, primary & HEPA filters, and control switches.

• Ambient air passes through the primary filter and is pressurized into the plenum chamber by the centrifugal fan.
• The air then undergoes HEPA filtration and is discharged from the top diffuser plate as clean airflow.
• The clean air continuously mixes with and dilutes the ambient air, achieving a purification effect.

Cabinet System

• Constructed from 304 stainless steel or powder-coated steel plates, with seamless welding for airtightness.
• Dual-door interlock mechanism (mechanical/electronic) to prevent cross-contamination.
• Built-in tempered glass viewing window, with optional UV sterilization lamp.
• Removable stainless steel dust collection tray at the bottom.

Air Handling System

• Centrifugal fan: Typically a multi-wing type (airflow 1200-2000 m³/h).
• Filtration system:Primary filter (G4 grade): Captures particles ≥5μm, protecting the HEPA filter.
• HEPA filter (H13-H14): 99.97-99.99% filtration efficiency @0.3μm.
• Plenum chamber: Designed for uniform air distribution.

Control System

• Microprocessor-based control panel.
• Adjustable air shower time (10-999 seconds).
• Differential pressure sensor for filter status monitoring.
• Photoelectric sensor for automatic activation.

Additional Configurations

• V-shaped airflow nozzles (wind speed ≥20 m/s).
• Built-in sterilization lamp (UVC or ozone optional).
• Conveyor belt system (for large pass-through units).

Air Purification Cycle

• Pre-filtration: Ambient air passes through the primary filter to remove large particles.
• Pressurization: The centrifugal fan forces air into the plenum chamber.
• HEPA filtration: Air is purified to ISO Class 5 (Class 100) cleanliness.
• Turbulent cleaning: The top diffuser plate creates uniform vertical airflow (20-25 m/s).
• Particle removal: High-speed airflow removes ≥99.5% of particles ≥0.5μm from surfaces.

Pressure Differential Maintenance

• Maintains positive pressure (+15Pa or higher) inside the chamber.
• Acts as an airlock to protect cleanroom pressure integrity.

Dynamic Purification Process

• Particle concentration decays exponentially: C = C₀e^(-nt) (where n = air change rate).

• Simultaneous material transfer and surface decontamination.
• Reduces particle introduction by 90% compared to standard pass boxes.
• Suitable for Grade B → Grade A cleanroom transitions.
• Complies with GMP dynamic cleanliness requirements.

This equipment utilizes forced convection cleaning to enable real-time purification during material transfer, overcoming the limitations of traditional pass boxes that rely solely on static self-cleaning. It is a standard configuration in modern cleanroom logistics systems.